Hiking · Preparation before routes
Plan Around Changing Ground Conditions
Volcanic trails combine mountain hazards with ones you will not meet elsewhere: gas, unstable ash slopes, hot ground and eruptions that can change a route overnight. Good preparation starts with today's official status, not the trail description.
Visitor checks · Before every outing
Five checks that come before the route
- 1 · Official status today
Read the latest bulletin from the volcano observatory and the notice from the park, municipality or civil protection. Note the date and time on each.
- 2 · Legal access
Confirm closures, exclusion zones, permit systems and guide requirements. On Etna and Stromboli, summit limits are set by ordinances that change with activity.
- 3 · Gas and wind
Check the wind forecast and any gas advisories. If you have asthma or heart or lung conditions, take official health advice seriously; some agencies recommend avoiding gas-affected areas altogether.
- 4 · Mountain weather
Summits generate cloud, wind and sudden cold. Visibility loss on featureless lava is a common cause of rescues.
- 5 · Plan and tell
Set a turnaround time, carry offline maps, and leave your route with someone. In Iceland, Safetravel lets you register a travel plan.
Alert levels · USGS example
What the levels mean
| Ground | Aviation | Meaning |
|---|---|---|
| Normal | Green | Typical background activity |
| Advisory | Yellow | Elevated unrest above background |
| Watch | Orange | Heightened unrest or minor eruption |
| Warning | Red | Hazardous eruption under way or imminent |
Other countries use their own scales: New Zealand's runs from 0 to 5, Indonesia's from I to IV. Always read the local definition, and remember local hazards such as gas or steam explosions can occur at any level.
Field note · Terrain
Why volcanic ground is harder than it looks
Volcanic slopes are often made of loose material sitting at its natural angle of rest. Cinder cones and ash slopes slide underfoot, doubling the effort of ascent and making descents fast and uncontrolled. Lava fields are the opposite: rigid but brutally uneven, with sharp edges, hidden cracks and collapsing crusts. On both, a sprained ankle far from a road becomes a rescue.
Altitude adds to it. Etna's summit area lies above 3,000 m, Villarrica stands at around 2,800 m, and Andean volcanoes go much higher. Cold wind on exposed ridges, glare off snow and ash, and dehydration in dark, heat-absorbing terrain all appear on the same day.
Finally, the terrain moves. Eruptions bury trails; earthquakes open fissures; rain on fresh ash triggers mudflows (lahars) along valleys. Route descriptions, including ours, age quickly. Use them for planning, then defer to current signage and rangers on the ground.
What to carry
Sturdy boots with protected ankles, long trousers, gloves for lava, layered warm and windproof clothing, at least two to three litres of water, sun protection, a headlamp, a charged phone and a paper map. Where authorities recommend them, carry a properly fitted gas mask or respirator, and know that a dust mask does not filter volcanic gases.
Timeline · A typical summit day
- Evening beforeRead bulletin, ordinance and forecast; confirm guide or permit.
- DawnRe-check status; start early to avoid afternoon cloud and heat.
- MiddayRespect your turnaround time whatever the view ahead.
- DescentSlow down on ash and scree; most slips happen going down.
- ReturnTell your contact you are back.
Route field notes
Compare settings →- Tongariro Alpine Crossing
Crosses Red Crater, the Emerald Lakes and the flanks of Ngāuruhoe. Te Maari erupted in 2012, damaging a hut on the route. Alpine weather turns quickly; shuttle bookings and parking limits apply. Check GeoNet and the Department of Conservation.
- Kīlauea Iki Trail
Descends through rainforest onto the solidified floor of the 1959 lava lake, still steaming in cracks. Trail status depends on summit activity; check the park's alerts.
- Fimmvörðuháls
From Skógar to Þórsmörk between two glaciers, crossing lava from the 2010 eruption. Long, exposed and subject to snow even in summer.
- Mount St. Helens, Monitor Ridge
A demanding scramble over boulders and ash to the crater rim. Climbing permits are required above 4,800 feet; cornices on the rim are dangerous.
- Etna summit area
Access to the summit craters is limited by ordinance and typically requires authorised guides. Lower areas such as the Silvestri craters are freely visited.
- Ijen crater
A pre-dawn ascent and descent into a crater with dense sulfur gas and an acidic lake. Closed during elevated activity; gas masks are essential where descent is permitted.